The invention relates to a spinning or twisting having a spindle shaft which, by means of a bolster and a step bearing, is disposed in a spindle bearing housing for which a holding device is provided which is applied in the area of the step bearing and is spring-elastically flexible essentially radially with respect to the spindle axis.
In the case of a known spinning or twisting spindle of the initially mentioned type (EP-A 0 209 799), the holding device comprises a sleeve mounted on the spindle bearing housing in the area of the step bearing and a sleeve which is arranged at an axial distance to it, surrounds the spindle bearing housing at a distance and is used for fastening to a spindle rail. Between the two sleeves, a ring of axially extending bendable spring bars is provided which are arranged at a uniform distance. As a result, it is to be achieved that the spindle bearing housing can be deflected only radially with respect to the spindle axis.
In order to reduce running noises of spinning or twisting spindles of the initially mentioned type, it is provided according to commonly assigned U.S. Pat. application Ser. No. 07/606,724, filed Oct. 31, 1990 corresponding to German Application P 39 38 255.9, that a connecting element is arranged in the area of the step bearing between the spindle bearing housing and a housing surrounding the spindle bearing housing at a distance, which connecting element is designed as a point of discontinuity for the flow of structure-borne sound.
It is an object of the invention to construct a spinning or twisting spindle of the initially mentioned type such that the air-borne noises are reduced.
This object is achieved in that a spring-elastic connecting element is arranged between the spindle bearing housing and a sleeve-type housing which surrounds it at a distance and can be mounted on a spindle rail, which connecting element forms a point of discontinuity for the flow of structure-borne sound, and in that the space between the surrounding support housing and the spindle bearing housing is filled up to at least two thirds of the height of the spindle bearing housing with a medium which is viscous in a temperature range of approximately 20.degree. to 60.degree. C.
First, the invention is based on the recognition that the bolster, which normally contains roller bodies, is the main cause of the running noises. Even if the bolster has a high precision with respect to shape, and there is only little play in the area of the bolster, small deviations of the running surface cannot be avoided. These have the result that the roller bodies and thus also the spindle bearing housing are caused to perform vibrations. In the so-called flow of structure-borne sound, these vibrations are then transmitted to other machine elements which have larger surfaces that can vibrate and therefore increase the generating of noise. By means of the point of discontinuity, it is achieved that the flow of structure-borne sound is significantly reduced in this area so that vibrations of the spindle bearing housing are transmitted to other machine elements and particularly to the spindle rail only to a significantly reduced degree. The running noises are therefore essentially reduced to the spindle bearing housing as the source of noise. In this case, the sleeve-type housing which surrounds the spindle bearing housing acts as a shield. The additional filling of the space between the spindle bearing housing and the support housing with a viscous medium has the additional result that the vibrations of the spindle bearing housing are damped so that a further reduction of noise is achieved.
In a further development of the invention, it is provided that the spindle bearing housing has mass that is smaller than the outer support housing. As a result, it is achieved that the spindle bearing housing and the outer housing do not vibrate with the same frequencies so that the vibrations of the spindle bearing housing which are damped by the inserted medium also do not result in excited vibrations of the outer housing.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.